21 Nov
2009
21 Nov
'09
7:26 p.m.
You can alos
support 3" drives/disks. The Hitachi drives have a standard
34 pin SA400 interface, the ones that Amstrad used have a 26 pin
connector (IIRC) with the same signals on it. 3" disks do have an index
hole, the sensor is a light barrier there, not a signal on the spindle
motor, but I've never seen or heard of hard sectored disks.
So more or less the same technology as a 5.25" disc then -- a ~5mm hole
in the jacket, a ~1mm pinhole in the disc, and an optosensor in the drive.